Method and apparatus for cooling engine exhaust pipes

ABSTRACT

A METHOD AND APPARATUS FOR COOLING EXHAUST PIPES OF INTERNAL COMBUSTION ENGINES WHEREIN CARBON DIOXIDE, SOTRED IN LIQUID STATE, IS DISPENSED THROUGH A NETWORK OF CONDUITS AND RELEASED IN OR AROUND EACH EXHAUST PIPE TO COOL THE PIPE PREVENTING FIRE WHEN COMBUSTIBLE FLUID COMES INTO CONTACT THEREWITH.

169-45 XR 3,5 1,210 SR X XMFJ"? Feb. 9, 1971 B. w; WISEMAN, JR 3,561,210

I METHOD AND APPARATUST'OR COOLING ENGINE EXHAUST PIPES Filed Jan. 24-.1969 v i 2 Sheets-Sheet 1,

uyvENToR. Ben W. Wnsemon, Jr.

7 MaM 1971 a. w; WISEMAN, JR 3,561,210 7 METHOD AND APPARATUS FORCOOLING ENGINE EXHAUST PIPES Filed Jan. 24. 1969 2 Sheets-Sheet 2INVENTOR. Ben W. WIsemQn, Jr.

0 .-BY i Maw 1L1 ATTORNEY United States Patent O 3,561,210 METHOD ANDAPPARATUS FOR COOLING ENGINE EXHAUST PIPES Ben W. Wiseman, J12, 303 WallTowers-West, Midland, Tex. 79701 Filed Jan. 24, 1969, Ser. No. 793,695Int. Cl. A62c 3/00, 35/40 U.S. Cl. 60-31 17 Claims ABSTRACT OF THEDISCLOSURE A method and apparatus for cooling exhaust pipes of internalcombustion engines wherein carbon dioxide, stored in liquid state, isdispensed through a network of conduits and released in or around eachexhaust pipe to cool the pipe preventing fire when combustible fluidcomes into contact therewith.

BACKGROUND OF INVENTION The production of oil and gas wells is reducedby flow restrictions, caused by an accumulation of matter in the bearingformation and by closure of a fracture through which oil and gasnormally flow into the well. The production of the well is increased byremoving flow restrictions, reopening closed fractures, and by enlargingdrainage patterns.

Numerous techniques are employed to stimulate production. However, amethod commonly used consists of pumping fracturing fluid, usually oil,mixed with various chemicals and propping agents down the well and intothe formation. The high pressure fracturing fluid is forced through theformation in a direction opposite to that of normal flow of oil and thepropping agent, which is normally silica sand, is forced into thefracture and holds the fracture open thereby increasing the normal flowrate of oil and gas from the formation to the well.

Several trucks having large engines, pumps and mixing devices mountedthereon are employed for forcing the fracturing fluid into the well tofracture a formation. Engines are normally run wide open to delivermaximum horsepower to pump the fracturing fluid at very high pressureinto the well. Since the engines are running at maximum power, exhaustpipes become very hot and sparks are often blown from the end thereof.

When a line between the pumps and the well breaks, hydraulic forcescause the pipe to swing violently spraying the combustible liquidstherein over a large area. When the combustible fluid strikes the hotexhaust pipes of engines used for driving the pumps, a fire is startedwhich will often result in the destruction of equipment costing inexcess of one million dollars and greatly endangers the lives ofworkmen.

A break in the high pressure line usually begins with a small leak whichis visibly detectable and then a larger rupture begins to form whichultimately causes the oil to be sprayed upon the engines causing a fire.

Heretofore, no suitable device has been developed to prevent theeventuality of a fire when a line breaks While fracturing operations arebeing conducted on oil and gas wells.

SUMMARY OF INVENTION I have developed a method and apparatus for coolingthe exhaust pipes of internal combustion engines instantaneously whenthe danger of a leak is first detected, to prevent the ignition of oiland other combustible liquids when it is sprayed thereon.

The method which I have discovered comprises releasing carbon dioxide orother suitable coolant into the exhaust pipe of an engine, or into amanifold around the Patented Feb. 9, 1971 exhaust pipe, causing the pipeto be chilled to a temperature below that required to ignite oil.

The apparatus which I employ to carry out the method consists of acontainer in which carbon dioxide or other coolant is stored and anetwork of conduits connecting the container to each exhaust pipe oneach engine which is being utilized in the fracturing operation. A valveis positioned to allow the carbon dioxide to be released into the-conduits-when "a leak is first detected in the high pressure oil lineand the exhaust pipes are cooled before a major break has time to formin the oil line.

It is therefore a primary object of the invention to provide a method ofcooling the exhaust pipe of an engine in a very short period of time.Another object of the invention is to provide apparatus capable ofdelivering coolant to .the exhaust pipe of the engine in a very shortperiod'of time in suflicient quantities to cool the exhaust pipe.

A further object of the invention is to provide apparatus which isversatile and readily adaptable to cooling any number of exhaust pipesof any number of engines positioned at varying locations at a work site.

A further object of the invention is to provide apparatus for coolingthe exhaustpipe of an engine wherein the apparatus may be connectedquickly and easily to an exhaust pipe without interfering with the workto be done by the engine. 1. 1

A still further object of the invention is to provide apparatus forcooling the exhaust pipe of an engine which is of simple constructionrequiring minimum maintenance and inspection.

A still further object of the invention is to provide apparatus forcooling the exhaust pipe of an engine adapted to be readily connectableto the exhaust pipe of an engine regardless of varied designs ofdifferent manufacturers of engines.

A still further object of the invention is to provide apparatus forcooling the exhaust pipe of an engine having a high degree ofdependability.

A still further object of the invention is to provide apparatus forcooling the exhaustpipe of an engine which may be manufactured andinstalled at a reasonable cost making the use thereof economicallyfeasible for use in mobile operations lasting a few hours or a few daysand then moved to a different site.

Other and further objects of the invention will become apparent uponreading the detailed specification hereinafter following and byreferring to the drawing annexed hereto.

DESCRIPTION OF THE DRAWINGS The enclosed drawings of two embodiments ofthe invention are provided so that the invention may be better and morefully understood, in which:

FIG. I is a plan view showing a schematic layout of apparatus employedin a typical fracturing operation illustrating the relationship of myinvention associated therewith;

FIG. II is a simplified diagrammatic view of the network of conduitsconnected to the exhaust pipes of engines on a typical pump truck;

FIG. III is a partially sectionalized view of a distribution manifold;

FIG. IV is a side elevational view of a conventional exhaust pipeshowing a conduit connected thereto for cooling same;

FIG. V is a side elevational view of a conventional exhaust pipe similarto that illustrated in FIG. IV with a modified means for connecting aconduit thereto;

FIG. VI is a cross sectional view taken substantially along line VIVI ofFIG. IV; and

FIG. VII is a cross sectional view taken along lines VII-VII of FIG. VI.

Numeral references are employed to indicate the various parts shown inthe drawings and like numerals indicate like parts throughout thevarious figures of the drawings.

DESCRIPTION OF A PREFERRED EMBODIMENT The general layout of aconventional well fracturing operation will first be briefly describedas a framework for the description of my invention.

Referring to FIG. I of the drawing, numeral 1 designates a well borehaving a suitable control head mounted thereon connected to lines 2a, 2band 20 through which fracturing fluid is pumped at very high pressuresfor servicing the well to increase the productivity thereof.

Fracturing fluid, such as oil, is pumped from containers 4 toproportioning units 6 where sand, delivered by dump trucks 8, and otheradditives are accurately measured and mixed with the fracturing fluidand delivered to pumping units 10. Pumping units 10 are equipped withpumps which discharge fracturing fluid into lines 2a, 2b and 2c. Pumpingunits 10 may deliver from 40 to 50 barrels per minute and pressures mayexceed 20,000 p.s.i. in lines 2a, 2b and 2c.

It should be apparent that the number of proportioning units 6 andpumping units 10 will vary depending upon specific requirements at aparticular well. The primary consideration dictating the number of unitsnecessary for a given job is the horsepower of engines needed to achievethe required pressure and flow rate.

Each proportioning unit *6 and pump unit 10 has one or more engines 11mounted therein for providing the needed horsepower. The engines andpumps are usually mounted upon a truck or trailer making them easilymovable from one well side to another. It should be readily apparentthat other or additional equipment may be utilized.

As best illustrated in FIGS. I and II of the drawings, my inventionembodies apparatus for cooling the exhaust pipes 12 of engines 11.

Container is used as a storage vessel for carbon dioxide or othersuitable coolant. Carbon dioxide is sometimes used as a refrigerantbecause it is readily obtainable, has a low boiling point, and has ahigh latent heat of vaporization.

The critical temperature (the temperature above which no pressure, nomatter how great, can liquefy the gas) of carbon dioxide is '88"Fahrenheit. The critical pressure (the pressure which just sufiices toliquefy the gas at the critical temperature) of carbon dioxide is 1,073p.s.i. As temperature is reduced the pressure required to maintain thecarbon dioxide in the liquid phase is decreased.

Carbon dioxide is in the liquid state when maintained at 0 Fahrenheitunder 300 p.s.i. pressure, limits which may be readily achieved in thefield. Therefore, under normal operating conditions container 4 shouldbe refrigerated and pressurized to assure that the carbon dioxide ismaintained in the liquid phase to facilitate pumping at high velocity,using a conventional pump 19, through conduits or to allow the carbondioxide to be simply released into the atmosphere adjacent to theexhaust pipes 12 on each engine employed in the fracturing operation.

Conventional refrigeration means 17 and pressurization means 18 aretherefore operably connected to container 20 in a manner well known topersons having ordinary skill in the art.

A trunk line 21 consists of conduits 22, 26 and 32.

One end of conduit 22 communicates with the inside of container 20 andthe other end thereof is connected to shutoff valve 24.

Shutofi' valve 24 is of conventional construction having a passagewayextending therethrough which may be opened or closed as desired bymanipulating suitable closure means therein.

Valve 24 is connected by a conduit 26 to valve 28 which may be openedand closed by suitable actuating means such as solenoid or motor 30.Actuating means 30 is controlled by suitable electrical circuit as willbe hereinafter more fully explained.

Valve 28 is connected through line 32 to a distributing manifold whichhas a plurality of valved outlets 36 communicating with the insidethereof being connectable through branch line 38 to individual unitmanifolds 40.

Individual unit manifolds may be positioned adjacent each proportioningunit 6 and each pump unit 10 and has valved outlets 42 communicatingwith the inside thereof connectable through unit lines 44 to eachexhaust pipe 12 of each engine.

Conduits 38 and 44 are preferably flexible tubes capable' of carrying asufiicient quantity of coolant to chill exhaust pipes 12 when valve 28is opened.

In the particular embodiment of the invention illustrated in FIG. II ofthe drawing, distributing manifold 35 is a tubular member 34 havingopposite ends 35a and 35b thereof closed defining a closed chamber 34.Valves 36 are positioned in spaced apart relation along the length ofthe tubular member and may be manually operated individually to open orclose outlets 37 communicating with the inside of chamber 34'. A conduit38 extends between one of the valves 36 and one of the vehicles on thesite and is connected to an individual unit manifoldf40. Each individualunit manifold 40 and distribution manifold 35 is of similarconstruction. Unit manifold 40 has outlets 41 having valves 42 mountedtherein.

Preferably each flexible conduit 38 and 44 has a conventional quickconnect coupling 50, see FIGS. IV, VI and VII, whereby a suitable numberof conduits may be connected to manifolds 35 and 40 for supplyingcoolant to each exhaust pipe 12. Couplings may consist of a femalemember 52 having a J-slot 54 formed therein and being adapted to receivepin 56 on male tubular member 58 when the male member is inserted intofemale member 52 and rotated. Seals 60 are provided in female member 52to prevent leakage when pressurized fluid is pumped therethrough.

Couplings 50 may be of the type which automatically opens and closes avalve in outlets 37 and 41 if the use of such is deemed expedient.

In a preferred embodiment of the invention illustrated in FIG. IV, eachexhaust pipe 12 has a male tubular member 58 extending through the wallthereof and welded or otherwise secured thereto connectable through acoupling 52 to flexible conduit 44.

From the foregoing, it should be readily apparent that any number offlexible conduits 38 may be connected to the valved outlets 36 ondistribution manifold 35 to accommodate any number of vehicles or powerunits on the well site. Valved outlets 36 which are not to be used maybe closed. For example, if manifold 35 has twentyfive valved outlets 36and ten vehicles are on the site, fifteen valves would not be used andmay therefore be closed.

Any number of flexible conduits 44 may be connected to valves 42 onindividual unit manifold 40 depending upon the number of exhaust pipeson a given vehicle. It should be noted the use of manifolds 35 and 40facilitates connecting container 20 to each exhaust pipe of a varyingnumber of vehicles by merely attaching conduits 38, manifolds 40 andconduits 44 to accommodate each exhaust pipe 12.

From the foregoing, it should be readily apparent that shutoff valve 24is normally in the open position. When valve 28 is opened liquid carbondioxide will be forced through conduits 22, '26, 32, 38 and 44 and willbe released into each exhaust pipe 12, causing immediate coolingthereof.

'In a normal operation a vehicle 60 has pressure gauges and otherinstruments mounted therein for providing instrumentation of thefracturing operation. The instruments are connected through a conduit 62to the well 1. A supervisor directs his attention to the instruments atall times. It: is desirable that actuating device 30 for controllingvaltie 28 be operable from vehicle 60 adjacent the instruments mountedtherein.

Motor 30 is energized by a circuit consisting of a line 65 connected toone side of the windings of motor 30 and the other end thereof connectedto the negative terminal of battery 66. The positive terminal of battery66 is connected through line 68 to a contact 70a of switch 70 and the,other contact 70b is connected through line 72 to the opposite side ofthe windings of motor 30. It should beradily apparent that when moveablepole 70c of switch-: -7.0 engages contact 70a a circuit is completed,energizing the coil of motor 30, causing valve 28 to be opened torelease carbon dioxide into each exhaust pipe 12 of each' engine on thesite.

In some 'Qapplications it may be desirable that more than one means beprovided for releasing the carbon dioxide from container 20. As bestillustrated in 'FIG. '11, a bypass conduit 31 connects conduit 26- withconduit 32 for routing carbon dioxide around valve 28. A manuallyoperated valve 33 is disposed in line 31 and is normally in the closedposition. Carbon dioxide may be released into line 32by'opening eithervalve 28 or valve 33.

DESCRIPTION OF A SECOND EMBODIMENT Referringto FIG. V, if it is notdesirable to insert tubular member 58 directly into exhaust pipe '12 ofan engine, theg'tubular member 58 may be secured in a pipe 80 which maybe positioned around exhaust pipe 12 whereby the carbon dioxide will bereleased to the inside of pipe 801'for cooling the exhaust pipe withoutpuncturing the said': exhaust pipe.

From the? foregoing, it should be readily apparent that I have developeda method and apparatus for cooling the exhaust' pipe of an engine whichis simple and inexpensive to manufacture and use and which may bemanipulated in a minimum of time.

As soon as a leak is detected in pressure lines 2a, 2b

or 2c, switch 70 may be closed causing valve 28 to be opened, releasingcarbon dioxide upon each exhaust pipe 12 to coo'l same below thetemperature required to ignite the combustible fracturing fluid if it issprayed thereon.

Having described my invention, I claim:

1. In apparatus for cooling the exhaust pipes of engines, a container;carbon dioxide in the container; means communicating with the containerto maintain the carbon dioxide under pressure; means communicating withthe container to maintain the carbon dioxide under refrigeration;dispensing means for the carbon dioxide adjacent each of said exhaustpipes arranged to release carbon dioxide to ambient atmosphere on thesurface of the exhaust pipe; a conduit extending between thecontainerand the dispensing means; and means for controlling the flow of carbondioxide through the conduit.

2. The combination called for in claim 1 wherein there are a pluralityof dispensing means, at least one of said dispensing means beingconnected to each exhaust pipe; and a plurality of conduits extendingbetween the container and the dispensing means.

3. The combination called for in claim 1 wherein the conduit includes atrunk line having one end thereof communicating with the inside of thecontainer; distributbeing connectable between an outlet in theindividual unit manifold and one of the dispensing means.

5. The combination called for in claim '1 wherein the dispensing meanscomprises an aperture in the wall of the exhaust pipe and means toattach the end of the conduit in communication with the aperture.

6. The combination called for in claim 1 wherein the dispensing meanscomprises a tubular body arranged about the exhaust pipe having anaperture in the wall thereof and means for attaching the end of theconduit in 'communication with the aperture.

7. In apparatus for cooling exhaust pipes of engines, a pressurizedcontainer; carbon dioxide in the conainer; a trunk line having one endthereof communicating with the inside of the container; a control valvein the trunk line; actuating means operably connected to the valve; adistributing manifold connected to the other end of the trunk line;distributing outlets in the distributing manifold; a valve in eachdistributing outlet; branch lines, each having an end connectable to thedistributing outlets in the distributing manifold; individual unitmanifolds connectable to the other end of each branch line; unit outletsin each individual unit manifold; a valve in each unit outlet of eachindividual unit manifold; unit lines having ends connectable to eachunit outlet of each individual unit manifold; dispensing meansconnectable to the other end of each unit line, said dispensing meansbeing connectable adjacent to and communicating with an exhaust pipeofan engine whereby opening the control valve causes carbon dioxide tobe dispensed on the surface of the exhaust pipe for cooling same. I

8. The combination called for in claim 7 wherein the actuating meansoperably connected to the control valve is electrically operated; andwith the addition of an electrical circuit connected to the actuatingmeans; a source of electricity in the circuit; and a switch in theciruit whereby the switch may be manipulated to close the circuit toenergize the actuating means to open the control valve.

9. A method of cooling exhaust pipes of engines comprising maintaining asupply of liquid carbon dioxide refrigerating and pressurizing saidcarbon dioxide; and conveying and dispensing the carbon dioxide toambient atmosphere adjacent each of said exhaust pipes, wherebyexpansion of the carbon dioxide absorbs heat to cool the exhaust pipe.

' 10. The method called for in claim 9 wherein the carbon dioxide isreleased into each exhaust pipe.

11. The method called for in claim 9 wherein the carbon dioxide isreleased around the outside of each exhaust pipe.

12. In apparatus for cooling the exhaust pipes of engines; a container;coolant in the container; a trunk line having one end thereofcommunicating with the inside of the container; distributing means onthe other end of the trunk line; a plurality of outlets in thedistributing means; a valve in each outlet in the distributing means; aplurality of branch lines each being connectable to an outlet in thedistributing means; a plurality of individual unit manifolds, each ofsaid manifolds 'having an inlet connectable to an end of one of thebranch lines, each of said manifolds having a plurality of outlets; avalve in each outlet in the manifolds; a plurality of unitlines, eachline being connectable to an outlet in an individual unit manifold;dispensing means for coolant adjacent each exhaust pipe arranged todispense coolant on the surface of the exhaust pipe, each of saiddispensing means being connectable with a unit line; and means forcontrol ling the flow of coolant to the trunk line.

13. In apparatus for cooling exhaust pipes of engines, a source ofcoolant; means for refrigerating and pressurizing said coolant; adishtributing manifold connectable to the source of coolant, saidmanifold having a plurality of outlets; valve means in each of saidoutlets; means for controlling flow of coolant to the manifold;dispensing means connectable to the valve in the outlet of the manifold,said dispensing means being arranged to dispense coolant adjacent eachof the exhaust pipes for cooling the exhaust pipes.

14. The combination called for in claim 13 wherein the coolant is carbondioxide.

-15. The combination called for in claim 14 with the addition of meansto cool the carbon dioxide to maintain same in liquid state untildispensed from the dispensing means.

16. In apparatus for cooling heated exhaust pipes of engines used inwell servicing operations, a source of coolant; means for refrigeratingand pressurizing said coolant; an individual coolant dispenser adjacenteach of said exhaust pipes equipment in the vicinity of the well beingserviced; conduit means connecting each coolant dispenser with thesource of coolant; and means to circulate coolant through the conduitmeans to release coolant onto the exhaust pipes for reducing thetemperature thereof to a temperature lower than the temperature ofcombustion of fluids used in the well servicing operation 17. Thecombination called for in claim 16 wherein the coolant is carbondioxide.

References Cited UNITED STATES PATENTS 1,653,604 12/ 1927 Schroder 60312,737,249 3/ 1 95 6 Pinkel 60--3l 2,857,005 10/ 11958- Medlock 4 169-23,012,613 12/1'961 Diquattro 169-2 3,016,956 1/ 1962 Olandt l691l2,143,311 1/1939 Geertz 16911 FOREIGN PATENTS 628,738 9/ 1949 GreatBritain 16911 DOUGLAS HART, Primary Examiner U.S. Cl. X.R. 6020; 169-2,11

22 3 3 UNITED STATES PATENT OFFICE CERTIFICATE OF CORRECTION February 9,1971 3,561,210 Dated Patent. No.

Inventor-(s) Ben W. Wiseman, Jr.

It is certified that error appears in the aboveidentified patent andthat said Letters Patent are hereby corrected as shown below:

Claim 7, line 2, change "conainer" to read container Claim 9, line 2,after "carbon dioxide" insert a semicolon.

Claim 13, line 3, change "dishtributing" to distributing Claim 16, line5, cancel "equipment" Signed and sealed this 8th day of June 1971 (SEAL)Attest:

WILLIAM E. SCHUYLER, JR

EDWARD M .F'IE'I'GHER JR Commissioner of Patents Attesting Officer

